The present invention relates to lubricants for engines, especially hydrogen-fueled internal combustion engines.
In the quest to improve air quality and comply with strict emission limits, many engine and vehicle manufacturers are exploring the use of hydrogen, in particular “neat” or pure hydrogen as a fuel for internal combustion engines. Many experts suggest hydrogen as an alternative fuel capable of furthering energy self-sufficiency and as an aid in securing renewable, affordable energy sources.
One of the environmental advantages of using hydrogen as a fuel is also a potential drawback. The product of combustion of hydrogen (apart from contaminants) is water, and in particular hot vaporous water. In part related to this phenomenon, burning hydrogen in an engine can create several performance-related challenges, including engine backfire on hot summer days, engine detonation (that is, misfiring or knocking) due to preignition, reduced sparkplug life due to deposit formation from the lubricant or contaminants, and corrosive or rust attack on piston rings, cylinder heads, and the combustion chamber generally, due to unusually high water content in the used oils. Also, combustion of hydrogen, as a gaseous fuel, may lead to higher levels of engine deposits.
Following extensive testing, the applicants have discovered a lubricant formulation which can be used to lubricate hydrogen-fueled engines while minimizing one or more of the above-mentioned problems and generally maintaining good engine durability, e.g., low wear.